I've had the Margaan Outpost crash before. It's a bug with his animation: he tries to start blacksmithing and the game crashes. I can't remember how I got around it...I think I used the Mad Companion Spell mod to catch him and put him on a different ai package (Relax instead of Free). That way he'd stop trying to work.

If I inactivate the "Unofficial Oblivion Patch" the crash dont appear just by running around down there, but if I talk to the two Dunmers down there the crash comes anyway short after quiting the dialogue menu.

Hmm, very interesting -- never had either problem before... are you using any of the fixes mods? If so, what version.

I'll try to reproduce the crash with the latest versions of all the fixes (v1.7).

UPDATE:

Both areas are working perfectly without any crashes for me with the Unofficial Oblivion Patch + Morroblivion v064 (plus with and without Morroblivion-Fixes and Morroblivion-Magic-Fixes v1.7). I have waited for over 6 minutes (which is 2 hours in game time) without any crashes. Talking to NPCs also does not produce any crashes. Watching the blacksmith do his hammer animation also does not crash.

1) If the blacksmith hammering animation is causing a crash, that probably means your files are corrupted and you need to do a fresh install. If it's still crashing after a fresh install, maybe the installation file itself is corrupted.

2) Please let me know which NPC you are talking to, what dialog topics you chose, and what they said (the last line of text is probably enough). The dialog scripts in the Elven Nations are very complex due to several quests taking place there... potentially, the crash is due to your save-file being corrupted and causing the wrong dialog and quest stage script to execute after talking to an NPC there.

My guess on my end is the presence of one or more dll files like Blockhead and OblivionReloaded that aren't reliant on an esp and influence the game's animations that has some conflict with Morroblivion's animation calling. Can't say for him, though. It was easier to just take his hammer away than spend hours troubleshooting...

Update: Inactivate the "Unofficial Oblivion Patch" didn't solve anything, it started to crash again when I return to the place later, when moving downstairs in the Elwens club (dont even have to talk to anyone....BANG!).

I restarted with new character, but crashing was the same.

I reinstall the Morroblivion v064, but still crashing.

I started to inactivate (the few) possible mods one by one. And when I inactivated "Morrowind_ob - UCWUS.esp" (+ 2 fixes) the crashing stop!

Been testing it all night (also been in Maargan outpost) and no crashing what so ever.

Another thing: Maybe the crashing is dependent on one of the Dunmer downstairs in the Elwen Club (I suspect the male one with the swords on his back), because at one time when I entered the club, he had moved himself almost upstairs on the ramp and the crash came as soon as I was close to him (Im still being upstairs!...only time the crashing been upstairs)

"Morrowind_ob - UCWUS.esp" is the Universal-Cast-When-Used-System -- the mod which manages the casting and recharging of nearly all Morrowind-based enchanted clothing/ring/amulets. It's very possible that something wrong with this file is causing all of your issues: (1) having trouble with recharging magic items (other thread post) and (2) having crashes in Elven Nations and Maar Gan when this mod is activated.

All versions of UCWUS work fine for me without any crashes. However, you may want to try out this version:

The guy falling from the sky in Seyda neen has ressurected somehow, he's stucked in a crusified position a few meters up in the air, naked. And the book is on the ground again (although I sold when I found it the first time)

My personality is at minimum, but most NPC greets me and smiles at me in the dialog menu (have high disposition towards me??)

Selling/buying prices and values for items, weapons and armor (both standard and enchanted) is very strange, when you look at weight, armor and damage.

In the quest "death of the taxman" (seyda neen), when you are facing and later attacked by the guilty dumner, and you start to defend yourself, his nord friend ("Braggart" something) also attacks you and when you defend yourself and finally kill this nord, the imperial guards will arrest you and other Seyda neen folks attack you (whats this all about??)

Items, dead NPCs seems to fall or sink into the ground, making it impossible to pick. Like a slave key that was suppose to be on top of a chest, had sinked into the chest. The thief ring in the cavers close to Seyda neen has sunk into the ground, you have to "scan" the area to find it (maybe this is simulating that it has been buried or something).

Also when I enter a lot of interior cells any items go "crazy" (often fishing pols) and fly around in the area.

The Death of the Taxman bit is due to how factions are setup in the Morrowind to keep NPCs from attacking each other incorrectly. It doesn't translate perfectly to Oblivion's system, so guards won't even attack bandits, etc...because they're in the same 0Morrowind faction to allow voices to play. I have the beta of a mod that Ponyrider0 started that tries to fix that...I need to finish it, lol.

The fallen wizard standing crucified thing is something you'll see in Oblivion sometimes with dead NPCs. I don't quite know why it happens. It's just a bug in the system. Punch the corpse and the Havok will restart.

"The fallen wizard standing crucified thing is something you'll see in Oblivion sometimes with dead NPCs"

yes, but the problem is that he "resurrect" every time I returned to the cell (after cell respawn time), just standing there in the air, naked and dead. And his book appears again and again on the ground. Have sold to Arriele the trader 5 books by now.